types: Migrate to stdplus hash

Trivial refactor to remove duplicate code.

Change-Id: I20ab453f9f85b5802ddcae0d389caf3b41381a86
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/src/system_queries.cpp b/src/system_queries.cpp
index 0ce674f..e922504 100644
--- a/src/system_queries.cpp
+++ b/src/system_queries.cpp
@@ -10,6 +10,7 @@
 
 #include <phosphor-logging/lg2.hpp>
 #include <stdplus/fd/create.hpp>
+#include <stdplus/hash/tuple.hpp>
 #include <stdplus/util/cexec.hpp>
 
 #include <algorithm>